The study is designed to improve the basis for diagnosis of pancreatitis, delineate its pathophysiology, describe its natural history and improve its treatment. Radioimmunoassay of pancreatic enzymes, glucagon, gastrin, parathormone, thyrocalcitonin, and insulin will be utilized tM study both acute and chronic pancreatitis. Pancreatography will be further developed for use preoperatively and operatively as a basis for operation for chronic pancreatitis. Fluid shifts and changes in vascular permeability will be studied in acute pancreatitis.